Martin, what you could do just to make it comfortable is to fit a shut off valve in the heater line going into the heater from the engine. Just get a small valve for liquids from NAPA or a farm service store and then fit the two female threaded ends of the valve with two metal ends that will screw into the valve and the other end will take a slip on hose with a hose clamp. Remember that the end pieces have to be the correct size to fit the threads of the valve and must be able to slide into the heater hose. Then in those seasons when you don't need or want heat in the car, just turn the valve to the closed position. In cold weather you would leave it open. I am a school bus driver and all our buses are so equipped because the heaters are large and the heater control valves just don't always work very well. That would be the easy and low cost solution to the problem. Of course the proper way would be to overhaul and repair your heater and AC controller, but that can't be difficult and expensive.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!